Group 4 Octahedral Complexes Catalyzed the Stereoregular and Elastomeric Polymerization of Propylene

摘要

Some group 4 octahedral complexes with different ligations (benzamidinate, acetylacetonate, β-diketoimidinate, phosphinoamide) have been synthesized. We demonstrate that early transition metals with a cis-octahedral geometry, when activated by methylalumoxane, catalyzed the Stereoregular polymerization of propylene, which can be modulated by pressure. The mechanism of formation and structure of the new type of elastomeric polypropylene obtained is discussed.